JPS6231555Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention comprises an upper flange, a lower flange having a bottom width narrower than the width of the upper flange, and a part of the lower flange that becomes wider than the bottom width as it reaches the upper flange. is formed into a T-shaped cross section by a web having an upper inclined part included in the upper flange and a lower inclined part which becomes wider as it reaches the lower flange, and the web has an intermediate part in the longitudinal direction of the girder. A lateral tightening diaphragm having a width equal to the bottom width is formed at both ends of the web in the girder length direction, and enlarged portions are formed at both ends of the web in the lengthwise direction, and the width increases from the web width to a width equal to the bottom width as it approaches the end side. , and relates to the improvement of formwork used for manufacturing PC girders in which prestressing prestressing prestressing prestressing prestressing steel materials are embedded by post-tensioning.

The above-mentioned so-called post-tension T-type PC girder has standardized cross-sectional dimensions, that is, the width and thickness of the upper and lower flanges are constant, and the web width and vertical height (i.e. girder height) are fixed. is standardized into multiple types.

However, the girder length, the positional relationship of the lateral tightening diaphragm with respect to both sides of the web, the position and length of the expanded section, etc. vary from site to site.

For this reason, conventionally, a wooden formwork made of water-resistant veneer and bone plates was used as a formwork for manufacturing PC girders in order to easily cope with changes in the shape of the web. Not only does it take a lot of time to assemble and dismantle the frame, but the material is not durable, and due to repeated water absorption and drying, and rough handling on site, the formwork can be used repeatedly 7 to 8 times. was a total loss (scrap).

In addition, highly durable metal formwork is sometimes used, but in this case, the manufacturing cost of the formwork is about twice that of wooden formwork, and the diaphragm for horizontal tightening varies depending on the site. It takes a lot of effort and costs to deal with changes in positional relationships, enlargement positions, lengths, and girder heights, so unless a large number of PC girders of the same shape are required, It was not profitable.

This invention uses a composite formwork made of wood and metal, which means that the formwork part for molding the part of the PC girder with constant dimensions is durable enough to be used many times. Made of highly durable metal, the formwork part for molding parts whose shape and dimensions change from site to site can easily cope with changes in shape, and
By using wood, which is inexpensive, the above-mentioned conventional drawbacks can be eliminated, and in addition, the disadvantages that are likely to arise by using wooden molds, namely, the wooden mold The purpose is to prevent concrete slag from flowing out of the formwork from the gap formed by the bending of the upper and lower parts of the frame part between the stiffeners.

That is, in the present invention, a first mold part for molding the upper flange including a part of the upper side inclined part and a second mold part for molding the lower flange are made of metal, and the web is molded. The third formwork part for the purpose of the invention is made of wood, and the first and second formwork parts are separated into vertically divisible metal joining flanges provided on both ends of the girder length direction, and the girder length direction. They are connected via a vertically divisible metal stiffener provided on the outside of the intermediate portion, and a bone plate provided in the third formwork portion is connected to the joining flange and the stiffener, and further, the first The first and second molds each have a metal fitting that locks on the upper outer side of the third molding part adjacent to the molding part and the lower outer side of the third molding part adjacent to the second molding part, respectively. It is characterized by the fact that it is provided in the frame part, and due to this structure, it is not only easier to assemble and dismantle compared to wooden formwork, but also, as for the metal formwork part,
It can be used repeatedly many times, and
Since the part of the formwork that differs in shape and size from site to site is the wooden formwork, it is easier and cheaper to deal with changes in shape and size than if the entire formwork were made of metal. This has resulted in lower total costs than conventional wooden formwork or metal formwork.

Then, the metal fittings provided on the highly rigid metal first and second formwork parts are locked to the upper and lower outer sides of the wooden third formwork part, which is most susceptible to bending under the flow pressure of concrete. By the way,
This condition makes it easy to assemble and dismantle the formwork, effectively suppressing the deflection of the wooden formwork, and preventing concrete slag from flowing out from the joints of the formwork, which tends to occur due to the composite formwork structure. It is now possible to prevent

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a side view of a T-shaped PC girder A, in which prestressing is introduced by post-tensioning, and FIG. 2 shows its transverse plane. Figure 3 shows an elevated road in which the PC girders A are lined up in the width direction and constructed on pillars (not shown), the upper surface of which is paved with concrete B made of cast-in-place concrete, etc., and filled with concrete C. A cross section is shown.

4 and 5 show longitudinal sections of the PC girder A, respectively. Although the shape of one side of the upper flange 1 is different, as explained below, the upper flange 1,
It will be clear that the shapes of 1 are substantially identical at the molding surface.

Figure 6 shows the reinforcing bars 6..., the PC steel material 7 for introducing prestress by post tension, the sheath 8 containing it, and the PC for connecting the adjacent PC girder.
The buried state of the sheath 10 for inserting the steel material 9 is shown.

The PC girder A includes an upper flange 1, a lower flange 2 having a bottom width _l2 narrower than the width _l1 of the upper flange 1, and a web ₃ extending therebetween and having a width l3 narrower than the bottom width _l2 . It is formed into a T-shaped cross section.

The web 3 has an upper inclined portion 4 which becomes wider than the bottom width l ₂ as it reaches the upper flange 1, and a portion a of which is included in the upper flange 1 and reaches the lower flange 2. A lower side inclined portion 5 gradually widens to a width equal to the bottom width _l2 , and a horizontal tightening diaphragm 15 at the middle part in the length direction of the girder, each of which gradually becomes wider and becomes equal to the bottom width _l2 . …
The enlarged portions 16, 16 on both ends in the longitudinal direction of the girder are bulged out on both the left and right sides, and the PC after molding
Prestress in the longitudinal direction of the girder is introduced by tensioning the steel material 7.

The formwork for manufacturing the PC girder A is constructed by connecting a predetermined number of composite formworks 14 divided into a plurality of pieces in the girder length direction, and each composite formwork 14 has an upper part. First and second formwork parts 11 and 12 for molding the upper flange 1 and lower flange 2 including part a of the side inclined part 4, the upper and lower inclined parts 4 and 5, the diaphragm 15, and the enlarged part 16.
and a third mold part 13 for molding the web 3 comprising.

The first formwork portion 11 is entirely made of metal (specifically, made of steel, and the same applies hereinafter) except for the weir plates 19 facing both sides 1a, 1a of the upper flange 1, and the second The formwork part 12 is entirely made of metal, and the third formwork part 13 is entirely made of wood.

As shown in FIGS. 7 to 9, the first formwork portion 11 is a part a of the upper inclined portion 4.
A pair of left and right metal lower plates 18, 18 facing the lower surface of the upper flange 1 including crank-shaped joining flanges 17, 17 and a stiffener provided at both longitudinal ends thereof and at a longitudinally intermediate portion apart from each other. 2
0..., an angle member 21a and a flat bar 21b provided vertically apart from each other with respect to these rising portions, and left and right upper angle members 21a, 21.
A connecting member 22 such as a single pipe extending over a and a wooden weir plate 19 facing the side surface 1a of the upper flange 1 are arranged at an angle.

The second formwork portion 12 includes a lower plate 23 and left and right side plates 24, 24, each of which is made of metal and faces the lower surface and left and right side surfaces of the lower flange 2.
A frame 26 is provided on the lower surface side of the lower plate 23, and joining flanges 27, 27 and a stiffener are provided on the outer surface of the side plate 24 with the upper ends protruding upward. 28...
are provided corresponding to those of the first formwork portion 11.

Next, the third formwork portion 13 includes the outer surface of the web 3 (that is, the web body 29, the upper and lower inclined portions 4,
5, the diaphragm 15... and the outer surface of the enlarged part 16...
0 and the joining flange 1 of the first formwork portion 11
7 and a bone plate 31 nailed at a position corresponding to the stiffener 20, and the first and second formwork portions 1 are connected to each other via a spacer member 32.
1 and 12, their joining flanges 17 and 27 and stiffeners 20 and 28 are connected by bolts, and the bone plate 31 of the third formwork part 13 is connected to the flanges 17 and 27 and the stiffeners 20 and 28. By connecting bolts, a metal molding frame 14 is constructed, and by using this molding frame 14, the PC girder A shown in FIG. And as shown in FIG.
By contacting the PC girder A shown in FIG. 5 with only one side surface 1a inclined, a so-called lug girder is formed.
Formwork part 11 where PC girders A and A shown in the figure are substantially the same
It will be understood that although the shapes are partially different, the molded surfaces are substantially the same.

By changing the vertical height of the third formwork part 13 and changing the length of the spacer member 32 accordingly, the first and second formwork parts 11 and 12 can be used as they are. The length and phase of the diaphragm 15 can be manufactured by changing the cross-sectional and longitudinal cross-sectional shapes of the weir plate 30 and the bone plate 31 in the third formwork part 13. Or enlarged abdomen 16
Various types of PC girders A can be manufactured with different positions and lengths. That is, by changing the shape of only the third formwork part 13 while leaving the first and second formwork parts 11 and 12 in the same shape, various types of molds can be created.
It is possible to manufacture PC girder A.

The clamp mechanism 25 pivots a hook 35 to an angle 34 connected to the angle frame 26, and when the hook 35 is locked to an angle 36 connected to the side plate 24, the lower plate 23 is fixed to the angle 36.
A wedge 37 which is clamped between the hook 35 and the frame 26 is driven between the hook 35 and the angle 34.

It goes without saying that gables are provided at both longitudinal ends of the formwork 14, and these gables and composite formwork 1
4 through which the sheath 8 is inserted.

Each of the inclined lower side of the lower plate 18 of the first formwork part 11 and the upper side of the side plate 24 of the second formwork part 12 is engaged with the upper and lower outer surfaces of the weir plate 30 of the third formwork part 13. The locking fittings 33, 33 are welded together, and due to the fluid pressure of the concrete poured into the formwork 14, the upper sloped part 30a of the weir plate 30 moves downward and the lower sloped part 30b moves laterally outward. It is designed to prevent it from bending.

The locking fittings 33, 33 have upper and lower inclined portions 3.
0a, 30b are provided with recesses corresponding to the outer corners, and notches are provided in the joining flanges 17, 27 and the stiffeners 20, 28, respectively. It is provided over the entire length of 24 in the longitudinal direction.

In addition, the locking metal fitting 33 is made into a short piece, and it is connected between the stiffeners 20..., 28... and the stiffener 2.
0, 28 and the joining flanges 17, 27, and the cross-sectional shape of the locking metal fitting 33 can be modified in various ways. It is sufficient if it can prevent 30b from bending outward.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and Figure 1 shows a PC
FIG. 2 is a side view of the girder, FIG. 2 is a cross-sectional plan view thereof, and FIG. 3 is a sectional view of the elevated road. Figures 4 and 5 are PC
A cross-sectional view of the girder, Figure 6 is a cross-sectional view illustrating the reinforcing condition, Figure 7 is a side view of the composite formwork, Figure 8 is a cross-sectional view of the right half of the composite formwork, and Figure 9 is a cross-sectional view of the right half of the composite formwork. It is an exploded view. FIG. 10 is a partial cross-sectional view of a frame portion of another embodiment, FIG. 11 is an enlarged view of the X portion in FIG. 8, and FIG. 12 is an enlarged view of the Y portion in FIG. 8. 1... Upper flange, 2... Lower flange, 3...
Web, 4, 5... Slanted part, 7... PC steel material,
11, 12, 13...Formwork part, 15...Diaphragm, 16...Extended portion, 17, 27...Joining flange, 20, 28...Stiffener, 31...
Bone plate, 33... Locking metal fitting, A... PC girder, a...
Part of the upper slope.

Claims (1)

[Scope of utility model registration request] an upper flange, a lower flange having a bottom width narrower than the width of the upper flange, and an upper inclined portion that becomes wider than the bottom width as it reaches the upper flange, and a part of which is included in the upper flange. The web is formed into a T-shaped cross section by a lower side inclined part that becomes wider as it reaches the lower flange, and the web has a horizontal tightening part having a width equal to the bottom width at the middle part in the longitudinal direction of the girder. The diaphragm is also formed with enlarged portions that widen from the web width to a width equal to the bottom width as the diaphragm reaches the end side on both ends in the longitudinal direction of the spar,
and a formwork for manufacturing a PC girder in which prestress introduction prestress introduction prestressing steel material is embedded by post-tensioning, the first formwork part for forming the upper flange including a part of the upper side inclined part; The second mold part for forming the lower flange is made of metal, the third mold part for web molding is made of wood, and the first and second mold parts are provided at both ends in the longitudinal direction of the girder. It is connected via a metal joining flange that can be divided into upper and lower parts and a metal stiffener that can be divided into upper and lower parts provided on the outside of the middle part in the longitudinal direction of the girder, and a bone plate provided in the third formwork part. connected to the joining flange and stiffener, and further includes an upper outer side of a third formwork part adjacent to the first formwork part and a lower outer side of the third formwork part adjacent to the second formwork part. A composite formwork for manufacturing a post-tension T-type PC girder, characterized in that the first and second formwork parts are provided with metal fittings that are respectively engaged with the first and second formwork parts.